Sparking device.



PATENTBD MAR. 3l, 1908.

H. MAILLARD. SPARKING DEVICE.

APPLIOATION FILED 00T. 24, 1906.

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UNITED l STATES PATENT OFFICE. I

'HENRI MAILLARD, orraaia FRANCE. l

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Spe'oioation o! Lettera Patent.

Patented March. 31, 1908.

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To all whom 'it may concern:

Be it known that I, Hmm! MAILLARD, a

4resident of 155 Avenue Malakoff, Paris,

France, have invented a new and useful Improvement in Sparking Devices, which invention is fully set forth in the following specification.l

This application whlch isa division of my co-pending application Sr. No. 243,371, filed January 30th, 1905, is'directedl to improvements in sparking devices therein disclosed and relates more particularly tof electro-magnetic sparkin devices in which the igniting spark ls'pro uced between two me-Y tallic vsparking terminals, one being stationar in relation to the other, and both insu ated fromthe parts of the en ine. The

movable memberv 1s actuated by t 1e passa e of a current ythrough a coil in circuit .with t e two sparking terminals.

` The device may be used with primary or storage batteries, as Ain thc case of ordinarv sparking plugs operated byvan induction coil, or with a magneto or dynamo with continuous or alternating curre'nt. I prefer, however, to use the device with a magneto having a voltage of from thirty (30) to. five hundred (500) according to the speed of the engine in connection with my improved means for placing the armature of the ma veto in short circuit before the moment at w ich the magneto gives its maximum voltage and interrupting the short 4 circuit at a point near the maximum voltage, as described in ,my a plication Sr. No. 243,371., above re- ,IThe invention; has among its principal obsparking terminals between which the spark ,is produced,l livhile giving free movement to sisting ,the corroding effects of such condi-l c; tiene; to secure perfect contact .between the ;s arking terminals; to protect the parts of lt e devlce from the destructive action of particularly at' heat and also from shocks, the contacting parts ofthe terminals; and to generally improve the sparking device.

. vmetal plate 10 havin a ts tomore effectually msula'te, in a spark om the core member 4v ufig'fdevice of the kind mentioned, the metal` In order that the invention may more readily be understood, reference is had to the accompanying drawings, which areintended merely as illustrations to ai'd lin the descrip.-

^ tion of the invention'and not as defining t limits thereof, reference being had to the claims for this purpose.

Figure 1 is a view in longitudinal section of the initing device Fi s. 2l and 3 are sectiona views showin di erent constructions of the movable spar 'ng terminal; Fi s. 4, 5

fand 6 `illustrate in sectional view different forms of the sparkin -tip; and Fig. 7 is a View in longitudine section illustratin another arrangement of spring and termina Referring to Fi 1,. a magnet coil 1 of wire, havingLan msulatlon of heat-resisting material, suclf asI asbestos, is supported on a spool 2 of non-conducting material, within the centerof which is a two-membered iron core, consisting of a movable member 3 and a'stationary member 4. The latter member has at its lnner end a recess or chamber 5 for receiving a spring 6, which normally forces the movable member 3 outward and may be arranged to act on the latter by tensiont as 'shown in Fi 1,' or by pressure, as shown in Fig."7. In t e former case, the movable core member 3 is provided with a reduced extension 7 for receiving one end of the spring, the

other end of theisprin being secured in a socket 8v on the core. EThe outer end of the stationary coremember 4 extends beyond the ,face yof thecoil and is provided with a screw-thread for'enga g a retainin -washer 9. One end of the p u is provide with a indmg-post and nut 11:', and is insulated by a'plate l12 of mica or the'like, both of which are made fast tothe plug b means of screws 13,' only one' of which 1s s own, and which enters a metal disk 14 resting against the end face of the spool 2. Between this disk andlwasher'Q, and between the screw 1'3 and the washer is placedan incombustible insulating material such as asbestos or mica.

contact with the ldisk 14 and with the bindp ing-post through screw 13. The inner end of One of the free ends ofthe coiil 1 is in metallic i the end of an interiorly screw-threaded tube 16 of non-magnetic metal such as brass or copper.I The opposite end of this tube 1s provided with a retaining shoulder 17 against which rests-a double flanged ring 18 of 1nsulatin material, between the flan es of which 1s a threaded metal collar 19 or resuch as steatite, porcelain, or mica.

ceiving the interiorly screw-threaded supporting nut 20. This nut 20 has an exterior threaded hub 22 for securing the lug in the walls of the engine cylinder. T e interior of this head is also threaded to receive a bridge-member 23 in which the fixed terminal 21 is supported, and to also receive an annular retaining-ring 24 which, in connection with said bridge-member, retains a guide 25 of heat-resisting and insulating material, 26 is 8. plate of insulating material separating the end of tube 16 from the nut 20. `A metal Washer 5 in metallic contact with the tube 16 and with the other end of the wire coil 1, and rests on the insulating flanged ring 18.

Secured to the movable iron core member 3 is a terminal rod 27, the construction of which is one of the principal features of this invention. .lt is essential that this rod should resist corroding action of heated gases, especially that of air or oxygen, and should possess rigidity when heated to such temperatures as are` attained in a combustion engine. For this purpose T construct the rod of an outer shell or casing of a metal not readily corroded under working conditions, such as nickel, silver or the like, and with an inner stifiening core of steel or nickel-stoel, which will not readily warp or bend by action of heat under the conditions named. ln Fig. 2 I have shown a solid rod 28 of nickel or silver having an interior socket for receiving a steel or nickel-steel rod 29.4 The rod ma however, be a solid piece of nickel-steel. n Fig. 3 the entire core is of steel incased in a non-corroding metal.

l provide the end of the terminal rod 27 with a tip, preferably' of platinum, which will resist the corroding action of sparking. This sparking-tip may assume various forms and be made of various non-corroding metals such as platinum, gold, or the like, but the form preferred is shown in Figs. 5 and 6, where the tip 30 is of conical form and may or may not be provided with a stein 31 for assisting in its retention in the end of the steel core 29. This form of tip is peculiarly useful in this class of igniters or sparklugs, Where the terminals are brought togetiier in repeatedf'blows for the reason that the tip cannot be driven into its socket nor expelled therefrom. l may, however, employ a rod 32 of platinum or like metal centrally disposed in the steel case, as shown in Fig. 4. In order that the rod 27 may be guided into metal parts to plate 5',

contacting ositiojn with `terminal 21, guide 25 is provi ed, whichis heat resisting and a non-conductor of electricit To always insure a yiel tween the terminals and to maintain a uniform pressure, lincase the spring in a cavity of the stationary core where/ the spring will be protected from heat, which might weaken,

ding contact bewarp or distort the coil, and prevent its proper action. The magnetic coil is preferably rotected by a casing 23, and may be of meta f' From the above description the assembling of the device will be readily understood, and requires no further explanation, except to state that it may be readily put together and taken apart, and when assembled the parts willnot shake loose.

In operation the current may be assumed to enter at terminal 21, and pass to terminalrod 3,' which is normally springpressed against terminal 21, thence through the which is in metallic contact with one end of the magnet coil, through the coil which it energizes, and out at post 11. 'As a result of energizing the coil 1 the movable core 3 overcomes the resilience of the spring 6 and the current is interrupted and a spark is produced between the sparking-tips. The spring then restores the parts to their original position. By reason of the construction of the rod 27 it is enabled to resist corroding action at high temperatures without becomin deformed by the softening action of the eat. The fact that the rod is of non-corrodible metal permits the use -of a guide for the rod without danger of becoming fast therein by products of surface oxidation. The spring for normally forcing 'the contacts together is protected from heat by reason of its position within the iron core, thereby preserving its elasticity and form.

`What is claimed is 1. 1n an electromagnetic sparking device, a two-part iron core one of said parts being in yielding engagement with the4 other, said movable part supporting alrod of non-oxidizable metal centrally reinforced with a rod of heat-refractory metal, said second rod having a tip of non-oxidizable metal, a second terminal, and a support for the same out of metallic contact with said core.

2. In an electromagnetic sparking plug, a two-membered iron core one member being stationary and the other having a yielding connection with the first, a rod having an outer surface of non-oxidizable metal and a core 'of rigid heat-resisting metal carried by said movable member, and a cone-shaped tip of platinum terminating said rod.

3. In an electromagnetic sparking device, a nut having an externally threaded tubular projebting member for securing the same in a In testimony' whereof I have signed .this

combustlon engine, a. spark-terminal' su specificetion in the presence of tWo subporting bridge member removably secured 1n scribing witnesses.

the end of said projecting member, a spark- HENRI MAILLARD. l 5 terminal guide of insulating material, and a Witnesses: l

retaining ring for securing said guide in EMILE LEDRET,

place in said tubular member. v v H. C. COXE. 

